He collects coins. In Russia in every large city there are memorial complexes devoted to the Russian soldiers killed during World War 2. In every such a place there is a fireplace powered by a gas which makes the flame burning through every weather, everyday 24×7. There is a tradition among Russian people to throw coins there, they say the place keepers then collect the coins and buy flower so that there could be everytime fresh flowers laid around. This boys also collect the coins.

OMG! A rouble itself is smth like 3 US cents… And these coins are kopeeks, what is even less than that… 10 kopeeks is like 0.3 cents… Can You buy anything for that? I don’t think so… You need pounds of coins

If I counted correctly in the picture there is 3 roubles 89 kopeeks and a single metroticket cost right now 20 roubles in St:Petersburg. And as cops are so corrupted in Russia most propably the officer will take the coins from these children.